Veteran adventurer Sir Ranulph Fiennes sailed for the Antarctic on Monday, leading a team bidding to become the first to cross the continent in winter in what he has described as a trip into the unknown with no chance of rescue.

A band played as Fiennes set sail from Cape Town, due to reach the coldest place on Earth later this month to start the over 2,000 mile- (nearly 4,000 kilometre-) journey in March.

So far the furthest winter venture into Antarctica has been only 60 miles, in the early 20th century.

Hailed as one of the world's greatest living explorers, 68-year-old Fiennes said previous record-breaking expeditions had all been in the summer.

"We've been doing expeditions for a total of 40 years. We've broken a great number of world records. In Antarctica we've got two huge records, one in 1979 and one in 1992, but they are all in summer," he told AFP on Sunday.

In 1979 Fiennes crossed both poles and in 1992 he crossed the Antarctic unsupported.

"So we aren't any more expert than anybody else at winter travel. There is no past history of winter travel in Antarctica apart from the 60-mile journey. So we are into the unknown."

Fiennes, 68, became the oldest Briton to summit Mount Everest in 2009, according to his website. He has also crossed both polar ice caps, including the unsupported Antarctic bid.

The Antarctic has the Earth's lowest recorded temperature of nearly minus 90 degrees Celsius (-130 degrees Fahrenheit), and levels of around minus 70 are expected during the six-month crossing, which will be conducted mostly in darkness.

"This is the first time once we've gone out, all the aeroplanes, all the ships from Antarctica disappear for eight months, and we're on our own and then you're in a situation where you would die," Fiennes said.

The six-member ice team will be led by two skiers carrying crevasse-detecting, ground-penetrating radars and followed by two tractors pulling sledge-mounted, converted containers with the rest of the group, equipment, fuel and food.

"Anybody who leaves the vehicle and goes out on skis has to accept the fact that if things go wrong, they will die like people did 100 years ago," Fiennes said.

The team will do scientific research and wants to raise $10 million (nearly eight million euros) for blindness charity Seeing Is Believing.

In preparation for the trip, they tested in temperatures as low as minus 58 Celsius (minus 72 Fahrenheit) in Britain and minus 45 in Sweden.

Co-leader Anton Bowring, who will be aboard the expedition ship after the ice team leaves, described the venture as "one of the last, great polar challenges".

"The pundits, the clever people who know about Antarctica, are looking at this and thinking you know it might just be a bit crazy. So we will see," he said.

"I think we've worked at it for five years, we reckon we've just about covered all the possible problems."

The team is travelling on the ice-strengthened SA Agulhas, a retired South African polar research ship which is now a training vessel.

The group will set out from Crown Bay, crossing the polar plateau at an average height of 10,000 feet above sea level, aiming to cover 22 miles a day to reach McMurdo Sound in September.

Once there, they face a wait of up to several months before the ship can fetch them.

The expedition's website is: www.thecoldestjourney.org.